Michigan Motorsports LS1 Flexplate Adapter Spacer - Fits GM TH350 TH400 Conversion Flywheel LS2 LS3 LQ4 LT1 LS7 5.7 6.0 5.3 Camaro Firebird LS based engines using a TH350, TH400, Powerglide transmission. If using a curved flexplate you'll need this adapter spacer. Quality Michigan Motorsports Product Used on various LS Swaps and Conversions